Former House Speaker John Boehner said he'd vote for Donald Trump in the general election if he were the Republican presidential nominee, but he wouldn’t vote for Ted Cruz.

“Lucifer in the flesh,” Boehner called Cruz on Wednesday during a talk at Stanford University, the student newspaper reported. “I have never worked with a more miserable son of a b---h in my life.”

Boehner’s scathing remarks are the latest sign of Cruz’s poor relationships on Capitol Hill, which the Texas senator has attempted to turn in his favor as he campaigns against what he calls the “Washington cartel.”

Cruz and Ohio Governor John Kasich are trying to deprive Trump of a delegate majority in the waning weeks of the nomination race in order to force an open convention in July.

Boehner, a Ohio Republican who left office in 2015, said he was “texting buddies” with the billionaire Trump and had played golf with him.

Boehner also mocked Democratic front-runner Hillary Clinton, saying, “Oh I'm a woman, vote for me” to suggest she is campaigning on her gender, before adding she was accomplished and smart.

Cruz responded that Boehner’s Trump admission showed that he and his newly named running mate, Carly Fiorina, are the better outsider choice for the White House.

“I’ve never worked with John Boehner. The truth of the matter is that I don’t know the man,” Cruz told reporters in Fort Wayne, Indiana. “If I have said 50 words in my life to John Boehner, I’d be surprised.”

Bad Blood

This isn’t the first time Boehner has unleashed on Cruz: He’s previously called him a “jackass” and a “false prophet,” and his loathing of Cruz is legendary inside the Capitol.

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The tension is a result largely of Cruz’s drive to defund Obamacare in 2013, leading to a government shutdown. In Boehner’s final years as speaker, Cruz was his nemesis, often plotting with a breakaway group of conservatives—many of whom would later form the Freedom Caucus—in opposition to Boehner's hopes for big budget deals and an immigration overhaul that would ultimately allow most undocumented immigrants to stay in the U.S.

When Boehner released his immigration principles in 2014, Cruz quickly labeled it amnesty, and few Republicans outside of leadership were willing to publicly sign on.

Speaking at the California university on Wednesday, Boehner referred to Freedom Caucus members as “knuckleheads” and “goofballs,” and said his hero, former President Ronald Reagan, “would be the most moderate Republican elected today.”

Sometimes Boehner has had warmer words for Cruz. “Ted Cruz used to be my attorney a long time ago. A good guy. I don't always agree with him, but he's a good guy,” he said on Jay Leno's show in 2014, according to the Washington Post. The case was a suit against a lawmaker whom Boehner accused of violating wiretapping laws, according to the Post.

Boehner and Cruz never personally met in the course of the Texan’s representation, Cruz spokeswoman Catherine Frazier said Thursday.

In March, Boehner said that if no candidate received a majority of delegates on first ballot at the convention, he'd support his House speaker successor, Paul Ryan.

A spokesman for Boehner, David Schnittger, later said Boehner was speaking in hypotheticals and supported Kasich for president. Ryan has ruled out a bid for the nomination.

Schnittger on Thursday said the Stanford newspaper’s account was accurate. The Kasich campaign didn’t immediately respond to a request for comment.